58 
Alliance I. CRUCIALES. 
Essential Character. — Embryo curved. Albumen absent. 
This character completely cuts off the Crucial from all other Parietous 
alliances. It has no very positive external relation, but may be accounted as 
near Violales as anything else. 
Order XL. CRUCIFER.^. 1 
or [ The Cruciferous Tribe. 
BRASSICACEiE. J 
Cruciferi®, Juss. Gen. 237. (1789); DC. Memoire sur les Cruciferes {no date)’, Syst. 
2. 139. (1821) ; Prod. 1. 131. (1824) ; Lindl. Synops. 20. (1829) ; Bartl. Ord.Nat. 
261. (1830). 
Essential Character. — Sepals, 4 deciduous, cruciate. Petals 4, cruciate, alternate 
with the sepals. Stamens 6, of which two are shorter, solitary, and opposite the lateral 
sepals ; occasionally toothed ; and four longer, in peiirs, opposite the anterior and posterior 
sepals, generally distinct, sometimes connate, or furnished with a tooth on the inside. Disk 
with various green glands between the petals and the stamens and ovary. Ovary superior, 
unilocular, with parietal placentae usually meeting in the middle, and forming a spurious 
dissepiment. Stigmas two, opposite the placentae. Fruit a silique or silicule, 1 -celled, or 
spuriously 2-celled; 1- or many-seeded; dehiscing by two valves separating from the 
replum ; or indehiscent. Seeds attached in a single row by a funiculus to each side of the 
placentae, generally pendulous. Albumen none. Embryo with the radicle folded upon the 
cotyledons. — Herbaceous plants, annual, biennial, or perennial, very seldom suffruticose. 
Leaves alternate. Flowers usuidly yellow or white, seldom purple. 
Anomalies. Schizopetalum has 4 cotyledons; sometimes the petals are abortive. 
Affinities. This order is among the most natural that are known, and 
its character of having 'svhat Linnsean botanists caU tetradynamous stamens is 
scarcely subject to exception. It has a near relation to Capparidaceae, with 
which it agrees in the number of the stamens of some species of that order, in 
the fruit having two placentae and a similar mode of dehiscence, and in the 
quaternary number of the divisions of the flower. To Papaveraceae it is 
thought to approach in the number of the petals, an unusual number to prevail 
in dicotyledonous plants, and again in the structure of the fruit of some genera 
of that order, such as Glaucium and Chehdonium ; with the siliquose-fruited 
Fumarieae it has also some analogy, and even with the whole of that order in 
the number of its petals, supposing the common opinion of the nature of the 
floral envelopes of Fumarieae to be correct, or in the binary division of its 
flower, from which the quaternary is only a shght deviation, upon the hypothesis 
I have suggested in speaking of that order. But the totally different structure 
of the seed forbids Cruciferae to be associated in the same group with the 
latter. 
Cruciferae may be said to be characterised essentially by their deviation 
from the ordinary symmetry observable in the relative arrangement of the 
parts of fructiflcation of other plants, — deviations which axe of a very interest- 
ing nature. Their stamens are arranged thus : two stand opposite each of the 
anterior and posterior sepals, and one opposite each of the lateral sepals ; there 
being 6 stamens to 4 sepals, instead of either 4 or 8, as would be normal. 
Now in what way does this arise } is the whorl of stamens to be considered 
double, one of the series belonging to the sepals, and one to the petals, and, of 
these, one imperfect } I am not aware of any such explanation having been 
offered, nor do I know of any better one. It appears to me that the outer 
series is incomplete, by the constant abortion of the stamens belonging to the 
